Re: pageinspect get_raw_page() option to return invalid pages - Mailing list pgsql-hackers

From Peter Geoghegan
Subject Re: pageinspect get_raw_page() option to return invalid pages
Date
Msg-id CAH2-Wzk-He76J1y6NbQ6vv_tWKYwf7iyitXGbBJeYoaZeKPe-Q@mail.gmail.com
Whole thread Raw
In response to pageinspect get_raw_page() option to return invalid pages  (Andres Freund <andres@anarazel.de>)
Responses Re: pageinspect get_raw_page() option to return invalid pages
List pgsql-hackers
On Fri, May 4, 2018 at 11:41 AM, Andres Freund <andres@anarazel.de> wrote:
> Hi,
>
> Currently there's no convenient way to get a corrupted page (be it a
> checksum failure, corrupted pd_upper/lower or whatnot) via pageinspect's
> get_raw_page(). Given that pageinspect is kind of our tool to do inspect
> issues on a data level that's not so great.
>
> I therefore propose that we add an *option* that bypasses shared buffers
> and reads the underlying data directly. And then skips over the
> validation.  I'm not 100% sure if this should be done unconditionally,
> or only if the item wasn't found in cache. There's some coherency
> differences, obviously.

+1. This would be a good option for amcheck, too.


-- 
Peter Geoghegan


pgsql-hackers by date:

Previous
From: Andres Freund
Date:
Subject: pageinspect get_raw_page() option to return invalid pages
Next
From: Andres Freund
Date:
Subject: Re: pageinspect get_raw_page() option to return invalid pages